Clutch and speed control apparatus



R. R. STEVENS 2,580,367

2 SHEETS-SHEET 1 Ill 3 INVENTOR.

CLUTCH AND SPEED CONTROL APPARATUS Dec.'25, 1951 Filed Dec. 1, 1948 0 0m QM Y 2 S on T in. "8 $8 8 A v mm mp mm Q q Dec. 25,- 1951 v R R. STEVENS 2,580,367

CLUTCH AND SPEED CONTROL. APPARATUS Filed Dec. 1, 194a 2 Sl-iEETSSl-EET 2 INVENTOR.

Roy R. Stevens BY A T TORNE Y Patented Dec. 25, 1951 UNITED STATES ATENT OFFICE Roy R. Stevens, Forest Hills, Pa., assignor to Westinghouse Air Brake Company, a corporation of Pennsylvania Application December 1, 1948, Serial No. 62,884

13 Claims. (Cl. 192- 098) This invention relates to control apparatus. and more particularly to the fluid pressure type for controlling speed of a prime mover and selective operation of clutches for reversing direction of operation of a member, such as a propeller, driven by said prime mover.

Where the prime mover on a ship is operative in one direction only it is customary to employ forward and reverse clutches to connect the prime mover to the propeller, the selective operation of said clutches providing foroperation of said propeller and hence of the ship in either the forward or astern directions. To reverse the direction of operation of the propeller it is only necessary to disengage the one clutch and engage the other, as well known, but unless certain precautions are taken damage to the clutches and other parts of the power transmission is liable to occur. In other words, it is desirable that the prime mover and propeller be brought to a low speed, such as idling speed of the prime mover, before an operating clutch is disengaged and the other clutch is engaged, in order to minimize the possibility of damage. Moreover it may also be desirable to increase'the power of or fuel supply to the prime mover slightly while engaging a clutch in order to minimize 1 possibility of the engine stalling.

The principal object of the invention is therefore the provision of improved means for accomplishing the above results.

degree, and preventing any substantial increase in power or speed of the prime mover until after said other clutch is engaged to a chosen degree, such as substantially fully engaged, the possibility of damage to the clutches and other parts of the power transmission is minimized.

Another object of the invention is the provision of means which is automatically operative to prevent operation of a prime mover above idling speed with a clutch disengaged or engaged to less than a chosen degree, and to reduce the speed of the prime mover to idling in case of reduction in engagement of a clutch to less than a chosen degree, such as in case of failure of the clutch.

Other objects and advantages will become apparent from the following more detailed descrlption of the invention.

In the accompanying drawing; Fig. 1 is a diagrammatic view, partly in section and partly in outline, of a clutch and speed control apparatus embodying the invention; Fig. 2 is a partial plan view of an operators control device employed in said apparatus; Fig. 3 is a sectional view taken on line 3-3 in said device; and Fig. 4 is a diagrammatic view of a modification of the inven- According to this object I provide means which 7 is automatically operative, in response to reversing movement of an operators clutch and speed control lever to reverse the direction of rotation of the propeller or other load being driven, to reduce the power of or fuel supply to the prime mover to a degree to permit reduction in speed of the prime mover to a chosen low speed,

' such as substantially idling, while maintaining the driving clutch engaged so that deceleration of the prime mover will also decelerate the load, and to then disengage the driving clutch and engage the other clutch and at the same time as initiating engagement of said other clutch to provide, if desired, a temporary slight increase in speed or power of the prime mover as tion.

Description-Jigs. 1 to 3 As shown in Fig. 1 of the drawing, reference numerals I and 2 indicate, respectively, fluid pressure operable forward and reverse couplings or clutches arranged to connect a prime mover to a load to be driven such as the propeller of a ship. The prime mover and propeller are not shown in the drawing since such structures are so well known. Likewise the clutches I and 2 are not shown in detail, but they may be of any suitable type, such for example, as illustrated diagrammatically in U. S. Patent No. 2,420,856 issued to W. E. Brill et al. on May 20, 1947. The reference numeral 3 designates a motor operable by fluid under pressure to adjust the power or speed of the prime motor, as for example the fuel supply to a diesel engine, in proportion to the pressure of such fluid. The structure of this motor is not shown in the drawing since such structures are so well known, but if desired, reference may be made to U. S. Patent No. 2,383,277 issued to me on August 214945, which illustrates a motor particularly adapted for this use.

An operators control valve device 4 is provided for controlling supply of fluid under pressure to and its release from the clutches I and 2 for controlling engagement and disengagement thereof and also to and from the speed control motor for controlling operation thereof. The operators control valve device 4 comprises a casing with which there is associated a forward clutch control valve device 5, a reverse clutch control valve device 5, a self-lapping speed regulating valve device I, and an operators control lever 8 for selectively controlling operation of the devices 5, 9 and 1.

The forward and reverse clutch control valve devices 5 and 6 are of identical structure each comprising a fluid pressure supply valve 9, both of which valves are mounted in a common chamber Ill connected by a passage H to a fluid pressure supply pipe adapted to be supplied with-fluidat a desired pressure, such as one hundredpounds from any suitable source. The valve 9 is provided with a fluted stem extending through azbore in a partition wall into a chamber I3 which in the valve device 5 is connected to a forward pipe 14 while in the valve device 5 said chamber is open toa reverse pipe--l5,said valve being provided for controlling supply 'of fluid under pressure from chamber 19 to-ch'amber I3 and thence to the respective pipe. A plunger I6 is slidably mounted in the casing in coaxial relation to valve 9 and on the end opposite saidvalve is provided with a seat for'engagement by a fluid pressure releasevalve ll contained-ma chamber 18 which is open to atmosphere through apassage I9 and a chamber 2l within the casing. The'seat for engagement'by valve I9 encircles a passageway 20 extending-through plunger 16 and open at the opposite end of said plunger to chamber l3, whereby said valve-is adapted to control communication between said chamber, and hence pipe M or I5, and atmosphere. The plunger [6 is provided witha-solid central portion H for engaging the stem of valve 9 to effect unseating thereof. A spring 22 acts onvalve 9 to urge it to its seat, while a spring 23 acts on plunger to urge it out of contact with the stem of said valve into contact with a-shoulder 24 inthe casing. In chamber I8 there is a plunger 25 arranged to engage valve I! for seating same, said-plunger having a'guide stem 26extending into the casing chamber 27'. The stem '26 inthe-forwardandreverse clutch control valve devices 5 and G are arranged in parallel, spacedapart relation for engagement by opposite ends of a lever 28 whichat its center is fulcrumed on a fixed pin.29..

.Upon turning of lever28 in a counterclockwise direction the valve IT. in the forward clutch control valve device 5 will be seated against plunger I6 followed by movement of said plunger against spring 23 into engagement with the stem of the respective supply valve 9 which latter valve will then 'be unseated, whereby the pipe [4 will be disconnected from atmosphere by closure'of said valve l1 and openedto the fluid pressure supply pipe l2 by opening of said valve 9, so that said pipe 14 will become charged with fluid at the pressure (100.pounds) present in pipe l2. When the lever 28 is operated as just described the respective end thereof is moved away. from stem 26 of. the reverse control valve device 6 so that therein the valve 9 remains seated by spring 22, the plunger [6 isheld in contact with shoulder 24 by spring 23, and the release valve I! remains open opening the respective pipe l5 to atmosphere;

Upon return of lever 28 to the position in which it is shown inthe drawing, spring 22 in the for-. ward clutch control valve device 5' seats the respective valve 9 and spring 23 returns'plunger I6 therein into contact with shoulder 24 whereupon pressure of fluid in pipe l4 unseats valve I! to permit release of such fluid pressure, the parts of the reverse control valve device 6 remaining in the position opening pipe 15 to atmosphere.

If the lever 29 is rocked in a clockwise direction the reverse clutch control valve device 6 will operate to open the reverse clutch pipe l5 to the fluid pressure supply pipe l2, while upon return of said lever to the position in which'it is shown in the drawing said pipe will be opened to atmosphere to release fluid under pressure therefrom, the forward clutch control valve device 5 maintaining pipe l4 open to atmosphere during such operation as will be clear from above description.

The self-lappings'peed regulating valve device 'I'maybe' of any suitable structure embodying a control memberior plunger 30 operative upon downward movement from a normal position,

such as it is shown in the, drawing, to supply fluid A rock shaft '32 disposed above plunger I'm-is journaled'inthe casing in two spaced apart bearings 33. A cam 34 is mounted on shaft 32 between the' bearings 33 and has two like and oppositely arrangedcam surfaces- 35 joined by a recess 38 for engaging andreceiving, respectively,

one side of a power transmitting member3'l the 1 opposite side of which is in contact with plunger With the cam 34in a neutral position for 39. recess 39 receiving the end of member 31 the control member- 39 of the self-lapping speed control" valve device: 1 will assume its normal positionto open pipe 3! to atmosphere. Rotation of rock shaft 32*and thereby of the cam element 34 in either directionfrom neutral position will displace the control-member 3fl'downwardly for actuating the device I to supply fluid from pipe 12 to the-speed-controlpipe 3| at a pressure proportional to-theextent of such movement.

Opposite the cam recess 36, the cam 34 has two spaced apart parallel arms 38 between which extends one end of the operators control lever 8. A bolt extends through the arms 38 and lever 9 .thereby'pr'oviding for rocking movement of said lever lengthwise of the rock shaft 32. Movement ofislever 8 rcircumferentially of rock shaft 32'.will:actuate cam element 34 for controlling the speed control .valve device I.

The rock shaft 32 has anaxial bore'in which is slidably mounted a plunger 4| having a slot 42 aligned with a relatively long opening as through one side of rock *shaft' 32.- The inner end of the operators control lever B extends through the opening 43 into the slot 42 and within said slot is .connected to. plunger 4! by a pin 44' secured in said plunger: Rocking of lever B in either direction'from a neutral position in which it is shown, lengthwise of the rock shaft 32 on bolt will therefo're move plunger 4! lengthwise within the rock shaft'32.

The lever 28for operating the forward and reverse clutch control valve devices 5 and 6 isprovided with an extension 45 the end of which is a cover46'having a slot 41 in which the operators control lever is arranged to move. The slot 41 has a 'centralportion 48 providing for movement of the lever 8 lengthwise of rock shaft 32 for. controlling the forward and reverse clutch control valve devices and 6 while retaining said rock shaft in neutral position against movement. At the opposite ends of the portion 48 of slot ll, said portion opens to oppositely extending portions 49, 49a providing for movement of said lever to rock shaft 32 in either direction from neutral position without effect upon position of plunger 41.

1 The pipe [4 is connected to a coupling or clutch.

interlock valve device 59 through a device 5| including a choke 52 for restricting flow of fluid under pressure in the direction from device 59 through said pipe and a communicationof greater flow capacity than and by-passing said choke and containing a check valve 53 for permitting a more rapid rate of flow of fluid under pressure in the opposite direction. The pipe is connected to a coupling or clutch interlock valve device. 54 through a device 55, said devices being like the devices 59 and 5|, respectively. These clutch control valve devices 59, 54 are also con.- nected respectively to the forward end reverse clutches I and 2 by pipes 56 and 57.

Each of the clutch interlock valve devices'59, 54 comprises a casing having a chamber 58 open to the respective pipe 56 or 51 and containing a valve ,59 for controlling communication between said chamber and a chamber 60 which is open to atmosphere through a pipe 6|. The valve 59 is provided on one end of a plunger 62 extending through chamber 60 and slidably mounted in the casing for a portion of its length, said plunger and valve being provided with communicating axialopenings 63 forv connecting chamber 58 to a chamber 64 at the opposite end of the plunger. Around the opening 63 on the end of plunger exposed to chamber 64 is a valve seat arranged for cooperation with a valve 65 contained in said chamber for controlling communication between said chamber and chamber 58. The chambers 64in the two clutch interlock valve devices 50, 54 are open, respectively, to pipes l4, I5.

Each of the interlock valve devices 59, 54 fur- Q ther comprises a flexible diaphragm 66 atone side of which is a pressure chamber 61. In the valve device 59 chamber 61 is open' through pipes 68 and 69 to the reverse clutch pipe 51, while in valve device 54 said chamber is open through bore in a partition wall 15, separating said cham-- her from chamber 64, into the latter chamber wherein the end of said stem is connected by a hook vI6 to the valve 65 whereby said valve is movable with said stem. A control spring ""1 contained in chamber [2 acts on the follower 13 and thereby the one side of diaphragm 66 with a chosen degree of force, for example such as to prevent, movement of said diaphragm from theposition in which it is shown in the drawing by fluid in chamber 61 at a pressure less than ten pounds. With the diaphragm 66 inthe position shown in the drawing the valve 59 is adapted.

to be seated byv a spring 18a and the valve 65 is adapted to be out of seating engagement with theend of plunger 62. When fluid at a pressure in excess of for example ten pounds is effective in chamber 61 the diaphragm 66 is adapted to deflect against spring fl! and seat valve 65 against.

plunger 62 and actuate said plunger to unseat valve 59.

The numeral I8 designates a coupling or clutch-speed interlock valve device arranged to control communication between the speed control pipe 3| and a pipe 19 connected to the speed adjusting motor 3. I The construction of the interlock valve device 18 is identical to that of the clutch interlock valve devices 50, 54 except that the spring 11 therein exerts a force against the diaphragm 66 such as to prevent deflection thereof to seat the valve and unseat the valve 59 by fluid in the chamber 61 at a pressure less than for instance sixty pounds. In the valve device 18, the valve chamber 58 is open to pipe 3!, the valve chamber 66 is open to pipe 19 and the diaphragm chamber 6'! is open to apipe connected to the side outlet of a double check valve device 8| comprising a double check valve 82 arranged to be operated byfluid under pressure from either one of pipes 69 or H, when the other pipe is vented, to open pipe 89 to the one of said two pipes supplied with fluid under pressure and to close communication between pipe 80 and the vented one of said two pipes.

Operation-Figs. 1 to 3 In operation, assume that pipe I2 is supplied with fluid at the desired pressure, such as one hundred pounds. Further assume that handle 8 of the operators control device 4 is in neutral position in which it is shown in Figs. 1 and 2 of the drawing. With handle 8 thus positioned the speed control pipe 3| is open to atmosphere through the speed regulating device I, and the forward and reverse clutch control pipes l4, l5 are open to atmosphere through the forward and reverse clutch control valve devices 5 and 6, respectively. Assuming that the parts of the clutch interlock valve devices 50, 54 are in the position, in which the parts of device 56 are shown in the drawing, pipe 56 and thereby the forward clutch I will be vented to pipe I4 through the open valve 65 in the interlock valve device 50, and pipe 51 and the reverse clutch 2 will likewise be vented to pipe l5 throughthe open valve 65 in the interlock valve device 54 whereby both clutches I and 2 will be disengaged. With pipe 56 vented diaphragm chamber 61 in the interlock valve device 54 will be vented thereto through pipes 10 and H to permit the parts of said valve devices to assume the position just mentioned, while with pipe 57 vented diaphragm chamber 61 in the interlock valve device 50 will be vented through pipes 66 and 69 to permit the parts of interlock valve device 50 to also assume the position just mentioned. With pipes H and 69 vented, pipe 89 and thereby diaphragm chamber 61 in the clutch-speed interlock valve device 18 will be vented past the double check valve 82 and one or the other of pipes H, 69. The parts of the clutch-speed interlock valve device 18 will therefore assume the position in which the valve 65 therein is unseated to open pipe 19 and the speed control motor 3 to atmosphere to permit adjustment of the power or speed of an operating prime mover to idling.

Now assuming that the apparatus is associated with a ship's propulsion system and that it is desired to move the ship forward, the operator will move control lever 6 from neutral position, in which it is shown in Figs. 1 and 2, to the righthand end of the portion 48 of slot 4? which will actuate plunger 4| and thereby lever 28 to seat valve I! and open valve 9 in the forward clutchaccess? 7. ontrol val eider c i rWhi e sti e. pantsn thereverse clutch control valve device 6 remaininthe position in which they; aregshown in the. drawing. With the forward clutchcontrolvalve device 5 thus O a d u dpn er; p essure .iro the supplypipe I2 will flow-to pipe Hand past. the :check valve 53 therein'to valve chamber 64 iii/the. Clutch interlock valve device 56, and, thence past the open yalver-et-toyalye chamber 55 ancl through Pipe 56120 the forward-clutchlto. actuatesameto connect the-prime mover to the propeller tosta rt the ship forward.

Fluid -under pressure-supplied to pipe '56 to engage the forward-clutch I will also flowthrough pipes ii .and to diaphragmchamber B'Iin the. clutch;.interioclc valve device 54 and when ten pounds pressure: is, obtained therein on diaphragm 56, said diaphragm will deflect to close the valve 65 and open' the valve .59.for: reasons which will be. later brought :out.

Fluid under pressure from pipe I I-will also flow past thedoublecheck valve 82 to pipe 8%, and diaphragm chamber- 67. t in the clutch-speed interlock valve device Wand whensuch pressure .is increased to the sixty pounds the diaphragm 65: therein will deflect to close the valve 65 and open the valve 59, respectively, for thereby disconnecting-pipe I9 and. the 1 speed;;ccntrol:motor. 3. from atmosphere; byway-of piped! and for opening pipe l9- and saidmotor to the speed. control pipe 3i. Movement of. the operators. control lever 8 from the right-handend of portion, 331.01. slot 41' into-- the portion 49 will; actuate. .the speed regulating device 1 tosupply fluid to pipe St at a pressure corresponding. tothe extent of such movement; and with pipe: 3i;:c onn ected to pipe 79, such iiuid pressure will become effective in the speedcontrol motor 3 to accelerate or increase the powerof the prime mover-to a corresponding degreeto move the ship forward.

it. may be moved without hesitation from neutral position to the desired'speed position. in, portion it of the slot and the same result will be obtained since, although fluid under-pressurewill immediately become effective in pipe 3i in-case oi the.

latter movement of said'lever, the-'ciutch-speed.

interlockv valve device 38 will prevent such iiuid becoming effective in the speed control motor 3 to accelerate the prime mover'until after :the

pressurein the forward clutch l is; increased to. thedegree (sixtypounds) to causesu-hstantialiy full engagement-thereof, whereupon ;the clutchspeed interlock valve device E8. wilLoperate to open pipe 3iv to. pipe 19 to permit-acceleration of the prime mover.

With theoperators control lever B in neutral positiontheship may be started astern by movement of said lever to the left-hand-endofportion Q8 of slot. 4? and then intoportionytfia in the same manner asfor startingithe ship forward. Now assume that theforward clutch I is engage-d and the speed'control motor3 is adjusted to cause iorwardmovement of the ship and that it is desired to reverse the direction of movement as promptly as possible. To accomplish this the operator will move lever 8 from whatever position it may be in in the portion 49 of slot 41 back to and through the portion 47 and into the portion 49a to a position corresponding to. the desired speed or power of the prime moverior astern l In starting the ship forward the lever B may be.

movement. of the ship. ;=In. responsel to "this move; ment, thespeed regulating .valveidevicez 'I-.-.--will operateto temporarily reduce z.slig'htlythe pressure in thespeed control pipe 3 I but promptlyreestablish such pressure. The forward :clutch.con trol valve device5 will operateto cut difsupply of fluid under pressure to pipe I4 and. to open said pipe to atmosphere, while the. reverse. clutch control valve device: 6. will be operated-. toopen the reverse pipe I5 to the fluid pressure supply pipe I2. Fluid under pressure will therefore .be supplied topipe I5 and past the check valve 53 tovalve chamber .64 in theclutch interlockvalve deviceS-l wherein it will be .temporarilyprevented from further. fiow by the respective .valve:65. which isseated by pressureof fluid .from theforward clutch pipe 56 acting inthe respectiverdiaphra'gm chamber 61.

.As fluid under pressure is releasedwfrom pipe I4 as just'mentioned, fluid under pressure willbe released'from theforwardclutch I through pipe 56. past the open valve 65 in the interlock valve device 50. and through choke 52 in device 5| to pipeM for releasing the forward clutch I, and also with such release fluid under pressurecwill be released from diaphragm chamber .61 in the clutch-speedinterlock valve-device "I8 and the clutch interlock valveclevicev 54. The spring: 71 in the clutch-speed interlock .valve device 'IB..will operatewhen the pressure. in:the forward clutch pipe .14 becomes reduced to sixty pounds to. disconnect pipe 19 from the speed control..pipe :3I-

and. to connect itto pipe. BI. whereby thefiuid under pressure will bepromptly released from the speed control motor 3 .for causing operation thereof to reduce the supply'of power or, fue1 to the prime mover. .to permit deceleration thereof t0,.a .low and substantially idling speed. .-With the clutch I still engaged deceleration of the prime mover will therefore. alsoocor-respondingly slow down the propeller. The choke -.-52 so limits the rate of release of fluid. under pressure from the forward clutch I thatthe speed of the prime mover and propeller will thus, becomel'reduced to a-chosen low degree; such as idling, by thetime the pressure of'nuid in theforward clutch I becomes reduced to a chosen low degree, such. as ten pounds, atwhic-hsaid clutch is substantially released. When the pressure of fluid in the forward clutchi, andhence in diaphragm chamber.

61 of the clutch interlock valvev device 54 becomes thus reduced to ten pounds, spring 11 in said interlock valve device will. actuate diaphragm .75

therein to permit closure of valve 59 and open-- ing of valve 65 therein. The closing ofvalve 59 in the clutchinterlock valve :device" 54 disconnects the reverse clutch 2 from atmosphere via pipe BI; and connects it to the reversez-pipe I5 which now is supplied Withfluidunder pressure by the reverse clutch control valve .device 6. Fluid under pressure therefore will then'fiow. from pipe I5 to pipe 51 andto the reverse clutch.2 to engage same. pipe 5'! it will become effective through. pipe 69 on thelowerend of the double check-valve 82. With the pressure on the opposite end of'the double check valve t2 reduced through pipe 56 to a lower degree, the pressure of fluid from'pipe 69 will move the double check valve'to its upper position to disconnect pipe from pipe 'II and device 318. When: the pressure of fluid in: the re- As pressure of fluid-isthus supplied to i verse clutch 2 and in chamber 61 of the clutchspeed interlock valve device 18 then becomes increased to sixty pounds, corresponding to a desired degree of engagement such as full engagement of the reverse clutch 2, the clutch-speed interlock valve device 18 will operate to seat valve 65 and open valve 59 therein, for thereby disconnecting the speed control motor from atmosphere and connecting it to the speed control pipe 3| which is supplied with fluid at a pressure corresponding to the position of lever 8 in portion 49a of slot 41. The speed control motor 3 will thereby be adjusted to increase the power or accelerate the prime mover and propeller to the degree selected by the position of the operators control lever in the portion 49a of slot 41.

In the operation of the apparatus to reverse the direction of movement of the ship from forward to astern as just described, the clutch interlock valve device 50 will operate in response to substantially ten pounds pressure in'the reverse clutch engaging pipe 51 to close the respective valve 65 and open the respective valve 59 whereby any remaining fluid present in the forward clutch I will be promptly vented to atmosphere past the valve 59 and through the atmospheric pipe Bl.

.With ten pounds pressure in either the forward clutch l or the reverse clutch 2, the clutch will be substantially released or ineffective, so that by quickly .dissipating this pressure remaining in the forward clutch l' at the time a like pressure becomes effective in the reverse clutch 2, the forward clutch will be substantially released before the reverse clutch starts to engage or become effective. Moreover this operation of the clutch interlock valve device 50 by pressure of fluid from the reverse clutch pipe 51 to quickly vent any fluid pressure still remaining in the forward clutch I also disconnects the forward clutch pipe 56 from the forward pipe 14 to pre' vent engagement of theforward clutch I 'until substantial complete release of the reverse clutch 2 in case the operator should move control lever 8 directly from the portion 49a of slot All to the portion 49 for effecting operation of apparatus l to reverse the direction of movement of the ship from astern to ahead. The operation of the apparatus in response to such movement of the operators control lever from the portion 49a to the portion 49 is the same as operation in response to movement of said lever from the portion 48 to the portion 49a of slot ll and hence it is not considered necessary to describe it in detail.

It is however desired to briefly point out'that when the lever 8 is moved from the portion 49 to the portion 490. of theslot 41 to effect operation of the apparatus to reverse direction of movement of the ship, that the clutch-speed interlock valve device 18 will promptly operate to cut off the supply of power or fuel to the prime mover to permit deceleration thereof and therevby of the propeller still connected to the prime The release of clutch I is promptly effect complete release of clutch I; the;-

clutch-speed interlock valve device l8, then oper' ating upon a chosen degree or substantially full engagement of clutch 2 'to permit increase in; power or acceleration of the prime'.moverand:

10 propeller to the selected speed. The operation of the apparatus is identical in reversing the direction of movement of the ship from reverse to forward. It will therefore be noted that upon operation of the apparatus to reverse direction of movement of a ship, the engaged clutch is held engaged to permit the prime mover to decelerate the propeller down to substantially idling speed of the prime mover whereupon the engaged clutch is promptly completely disengaged and the other clutch is engaged before the prime mover'is accelerated thereby minimizing wear of and possibility of damage to the clutches and other parts of a power transmission system.

With either clutch l or 2 engaged, if it is desired to effect disengagement thereof without effecting engagement of the other clutch, this may be effected by returning the lever 8 to neutral position, whereby the respective forward or reverse clutch control valve device 5 or 6 will be operated to open the respective pipe M or I5, and thereby the respective clutch l or 2, to atmosphere for effecting disengagement thereof.

While the clutch I or 2 is engaged and the prime mover is driving the load if the clutch engaging pressure in pipe 56 or pipe 5'! should for any reason reduce to below sixty pounds, it will be noted that the clutch-speed interlock valve device 18 will respond to such reduction and disconnect the speed control motor 3 from the speed control pipe 3! and vent fluid under pressure from said motor to atmosphere through the respective pipe 6| to thereby reduce the power and/or speed of the prime mover to cause idling thereof. This will not only call the operators attention to the failure so that it may be corrected, but will also minimize unnecessary, damaging slipping of the clutch which otherwise might result.

Description and operationFig. 4

At the time of engaging either clutch, in the structure shown in Fig. l of the drawing, the prime mover will be operating at idling speed and power, as above described. In order to minimize the possibility of the prime mover becoming stalled at the time of engaging either clutch it may be desirable to increase slightly the power or speed of the prime mover and this may be accomplished by the modification of the invention shown in Fig. 4 of the drawing.

Accordingto this modification, I add to the apparatus shown in Fig. l, a booster interlock valve device 85 which structurally may be identical to the clutch-speed interlock valve device 78 except for the spring ll employed in the device 7 85 which acts on the respective diaphragm 66 with a force to prevent deflection of said diaphragm with fluid in the chamber 61 at'a pressure less than for example twenty pounds. Diaphragm chamber 61 in the interlock valve device 85 is open to pipe8il through a pipe 86 in which there is disposed a choke 81, and pipe 6| from the clutch-speed interlock valve device 18 is connected to valve chamber 58 in the interlock valve 56 or' 51 and thereby in pipe and diaphragm chamber 6'! of the clutch-speedinterlock valve device 18 will position said"'device to openpipe 11 79 to the speed control pipe 3| to permitadjustment of the poweror speedof the prime mover by the operators control levert in the same manner as in the structure shown in Fig. l and above described. Under. this condition'the same pres-- sure will also be effective from pipe BU-through pipe 85 in diaphragm chamber 6'! of the inter-- lock valve device 85 and therein act to close the respective valve 65 and open the respective valve 56 whereby pipe from the clutch-speed interlock valve device 18 "will be open to atmosphere through pipe Bla.

When the lever 8 is moved to neutral position for releasing fluid under pressure from pipe 55 or pipe 5! to effect disengagement of the respective clutch I 'or. 2, and for releasing fluid under pressure from pipe 3! for reducing the power or speed of the primemover, -t l 1e clutch-speed interlock valve device 18 will operate when the pressure in pipe 55 ;or 51- -becomesreduced to sixty pounds "to disconnect-the speed control motor 3 from the speed control pipe 3! and open said motor to atmosphere'by way of therespective pipe 6|, the interlock valve device 85 ;and pipe fila until thepressurein pipe 55 or 5? becomes reduced to twenty pounds, whereuponthe inter: lock valve device 85 will operate to open pipe 5% to pipe 56. During the time the speed control motor 3 is open to atmosphere-by way of pipe Gla, the pressure of fluid in said motor will-become reduced sufiiciently, such-as to atmospheric pressure, to cause. the engine speed or power to reduce to substantially idlingor minimum, while upon subsequent operation of the interlock valve device 85 to open pipe 6f to pipe -83theremaybe a slight momentary increase in pressure inmotor 3 by fluid under pressure from pipe 5% orv 5'! which however will be quickly dissipated alongwith 'the'venting of fluid under pressure from' pipe 55 or 51 and have no material effect on engine power or speed;

Now let it be assumed that the prime mover is driving the ship" forward and that the operators control lever 8 ismoved from its 'posi'tion"in'the portion 49 of slot l'l to a'desire'd'power or speed position in the portion 43a to'effec't reversal of the ship. In response tothis movement pressure of fluid from'theforwar'd' clutc'l'i' l will be dissipated through the clutch interlock valve device 50 and-choke 52 as above described, in response to which reduction the clutch-speed interlock valve device 18 willop'erate in the same manner as above described'to'vent fluid under pressure from the speed control motor 3 by way of the interlock valve device 85, pipe lila and fohoke 88,- andcause operation of saidmotor to-reduce the I. power or speed of the prime mover substantiallyto idling. When the pressure" of fluid in the for ward clutch l becomes further-reduced to twenty pounds the interlock valve'device 85 will operateto connect the respective pipe Blto pipe 86 fol lowing which the clutch interlockvalve device 54*- will operate, when the pressure in the forward;- clutch becomes further reduced to tnpounds;

'65 [5 to the reverse clutch 2 to initiate engagement to establish communication from the reverse pipe of the reverse clutch 2. As fluid under pressure is thus supplied to pipe 5! and to the reverse clutch 2, the double check valve 82 will shift to open pipe 51 to pipe 80, so that asfluid under pressure becomes effective in the reverse clutch 2 it will also flow to pipe'83'andthence-tothe clutch-:-

speed interlock v Fluidunder pressure thus supplied to chamber 64 in-the interlock valve device will flowpast the open'valve 65 therein to the connected pipe BI and thence through the clutch-speed interlock valve device 18 to the speed control motor 3 and actuate same to correspondingly increase the power or speedof the prime mover, it being noted that this will occur immediately in responseto supply of fluid under pressure to initiate engagement of the reverse clutch 2 in order to prevent stalling of the prime mover incident to such engagement.

When the pressure of fluid'obtained through choke 81 in diaphragm chamber 67 of the interlock valve device 85 from the reverse clutch engaging pipe 5'! becomes increased to twenty pounds, said interlock-valve device will be operated to disconnect the speedcontrol motor 3 from pipe 85 and open it toratmosphere through pipe 6 la thereby limiting the pressure of fluid obtained in the speed controlmotor 3, and hence the increase in power or speed-of the prime mover at the time of engaging the reverse clutch, to a slightdegree only sufficient to accomplish the desired end of preventing the-prime mover from stalling.

When the pressure of'fiuid in the reverse clutch v Inreversingthe clutches as just described, it will benoted that choke 81 controls or restricts the rate ofsupply of fluid under pressure to diaphragm chamber 61 of the interlock valve device Hand to the speed control motor 3, the flow capacity'of' said choke being such as to insure operating of the interlock valve device 85 to cut ofi the supply of fluid under pressure to the speed control motor 3 the instant such pressure is increased'to the degree (twenty pounds) necessary to cause the desired increase in power or speed of the prime mover. Also in reversing the clutches; the pressure of fluid in the speed controlmotor 3 will be reduced to a chosen low degree, such as atmospheric pressure, between the time of re sponse: of the clutch speed interlock valve device" 18 and of the booster interlockvalve device 85 to i reducing pressure of fluid in either the forward or reverse'clutch'control pipe 56 or 5lto"efictdisengagement of the respective clutchand be'-" tween the time of response of the booster inter upon the result, the onlylpurp'ose being to sufii-i ciently retard release of fluid under pressure'fr'oni" the speed control motor 3 under the above conditions'to slightlyslow down its rate of operation which-occurs at substantially full engagement of the clutch. V

The-operation of the apparatus in response'to movement of the operator's control lever from? the portion 4912 bf" the-slot 41 the portion 49;" o to efiect reversalibf. $15 directien or'snipmove- 13 ment from astern to ahead issubstantiallythe same as above decribed for reversing ship movement from ahead to astem and need not therefore be described. I

Summary ver to preventengagement of either clutch until after the other clutch, is substantially disengaged, and in which neither clutch can be either engaged or disengaged with the prime mover and load operating at a speedrexceeding a chosen low degree, such as idling, whereby possibility of excessive wear of and damage ,to the clutchesv or other parts of the associated power transmission is minimized. Moreover the apparatus may embody structure automatically operative in reversing clutches to provide a slight temporary boost in engine power or speed to prevent stalling of the prime mover while engaging either clutch. The speed or power of the prime mover cannot be increased unless the pressure of fluid for engaging the clutches. can be increased above that required for operating the clutch-speed interlock, valve device, corresponding to a chosen degree of engagement of the clutches, and if, while a clutch is engaged, the pressure of the clutch engaging fluid should for any reason become reduced to a slightly lower degree, the operation of the clutch-speed interlock'valve device will reduce the power and speed of the prime mover to idling.

' Having now ,described my invention what I claim as new and desire to secure by Letters Patent, is:

1. An apparatus for controlling operation of two individual coupling control means adapted to be operated by fluid only at and exceeding a chosen pressure for connecting a prime mover to drive a load and for also controlling a power control motor adapted to be operated by fluid under pressure for adjusting the speed of said prime mover in proportion to the pressure of such fluid, comprising in combination with said coupling control means and motor, a control device for selectively supplying fluid under pressure to operate either one of said coupling control means and for at the same time supplying fluid under pressure to operate said power control motor and for releasing fluid under pressure from the other coupling control means, coupling interlock means operable by fluid in one of said coupling control means when in ex cess of said chosen pressure for closing the fluid pressure supply communication from said control device to the other coupling control means other interlock means responsive to fluid at less than a chosen higher pressure for closing the fluid pressure supply communication from said control device to said power control means and for opening a fluid pressure release communication from said power control means, and means operable by fluid pressure in said two coupling control means to selectively subject said other interlock means to pressure of fluidin the one of said coupling control means which is at the higher pressure. j

-2. Ari-apparatus for controlling operation of two individualcoupling control means adapted.

g is

14 to, be operated by fluid only at and exceeding a chosen pressure for connecting a prime mover to drive a load and for also controlling a power control motor adapted to be operated by fluid under pressure for adjusting the speed of said prime mover in proportion to the pressure of such fluid, comprising in combination with said coupling control means and motor, two coupling control pipes one connected to each of said coupling control means, a speed control pipe, a control device for supplying fluid under pressure to either one of said coupling control pipes, while at the same'time venting the othercoupling control pipe and supplying fluid under pressure to said speed control pipe, coupling interlock means controlling communication between said coupling control pipesand the respective coupling control means operable by fluid at or exceeding said chosen pressure in either coupling control means to close communication between the other coupling control means and the respective pipe and open said other coupling control means to atmosphere and responsive to a reduction in such pressure to a degree below said chosen pressure to open said communication, and coupling speed interlock means controlling communication between said speed control pipe and said power control motor operative to open such communication in response to pressure of fluid exceeding a chosen higher degree in either one of said coupling control means and to close such communication and release fluid under pressure from said power control motor in response .to

a lower pressure of fluid in either one of said coupling control means.

3. An apparatus for controlling two individual couplings operable by fluid under pressure to provide a driving connection between a load and a prime mover to a degree proportional to the pressure of such fluid and'operable upon release of such fluid under pressure to disconnect said load from said prime mover, and forv also controlling a power control motor operable by fluid under pressure to adjust the speed of said prime mover in proportion to the pressure of such fluid,-comprising in combination with said couplings and motor, two coupling control pipes one connectedto each of said couplings, a'speed control pipe for said power control motor, a control device for selectively supplying fluid under pressure to either one of said coupling control pipes while at thesame time releasing fluid under pressure from the other coupling control pipe and supplying fluid under pressure to said speed control. pipe,.two coupling interlock valve devices, one controlling communication between each of said coupling control pipes and the re speed control pipe and power control motor operable to open such communication in response to pressure of fluid in either of said couplings required to provide a chosen degree of engagement thereof and operable to close such communication and open said motorto atmosphere upon-a reduction in pressure of the controlling fluid to a lower degree;.and.means.for selectively opening said coupling speed interlock valve de grease vice =to"--the oneof said couplings supplied with at higher pressure? 45am apparatusfor control-ling two individual couplings' operable by fluid 7 under pressure to provide a-drivingpcnnection between a load and a pr'ime mover to a' degree-proportional to the pressure of such fluid and operableupon release of such fluidunder pressure" to disconnect said load from" said prime moverand for also controlling a power control motoroperableby fluid under pressure to adjust the speedof said prime -mover-in-proportion to the pressure of such fluid,

comprising in combination with said Couplings and niotor, a control device operable to selectively supply fluidunder pressure to either one of said-couplings and'at thesa-rne time release fluid under pressure from the other coupling and supply fluidunder pressure to operate said motor, means controlling the supply of fluid under pressure to and its releaseiromeach of said couplings operable'upon operation of said control device to release fluid under pressure from either one of couplings, todelay the supply of fluid under pressure to the other coupling until'the pressure of fluid in said one coupling is reduced to below a chosen pr essure, and clutch'speed interlock means operable in response-to a chosen higher pressure of fluid in either one of said couplings to open said power controlmotor to said control device and operable in response to a lower pressure of fluid to open said motor to atmosphere.

5.-:An ;apparatus for controlling two fluid pressure operable couplings for individually trans mitting power from a prime mover to a load in proportion to the pressure of such fluid comprisingain combination with said couplingsa control device'forselectively supplying fluid under pressure to' operate either one of said couplings while releasingfluid under pressure from the other coupling-,;interlock meanscontrolling the fluid pressure-supply and -release communication between said couplingsand 'control device operable upon operation of said control device to supply fluid underi-press'ureto operate either coupling to close said'communi'ca'tion with the pressure of fluid in power of said prime mover in proportion to the pressure of such fluid comprising in combination with said coupling, and motor, a control device for supplyingfluid under pressure to and releasing fluid under pressure from said coupling and motor; interlock -mearis controlled by pressure of fluid in said coupling for establishing'afluid pressurecontrol communication between said control de'vice and motor only when the pressure of the coupling fluid is 'im excess'of a chosen degree, other interlock means also responsive to pressure oP-fiuiddn'said couplingifor establishing a fluid pressure supply communication to'said motor only I when :the: pressure oflicoupling fluid is less than a chose'm lower rdegreep and means for i limiting pressure v ot fluidiin: the. "last named lcommunica 7. apparatus 'for' controlling operation of: a couplingoperable by fluid under pressureto transj mit power froma prime-mover to drive a load in proportion to the pressure of such fluid and for also controlling a motor operable by fluid under pressure to increase the speed or power of said prime mover in proportion to the pressure of such fluidcomprising in combination with said coupling and motor, a control device for supplying fluid under pressure to and releasing fluid under pressurejfrom said coupling and motor, two fluid pressure controlled'devices one responsive only to a pressure of fluid in excess of that required toproyide substantially full effectiveness of said coupling-to establish communication between said control device and motor and operative at a lower pressure to close said communication and establish another communication opening said motor 'to the other fluid pressure controlled device, said otherfluid pressure controlled device beingresponsive onlyv topressure of fluid inexcess of that required to initiate eflectiveness of said coupling to open said other communication to atmosphere and operative at a lower pressure to supply fluid under pressure to said other communication, and means for rendering both of said fluid pressure, controlled devices responsive to pressure of fluid s'uppliedfor operating said coupling means.

8; An-apparatus for controlling operation of a coupling operable by fluid under pressure to transmit power from a primemover to drive a load in proportion, to the pressure of such fluid and for also controlling a motor operablebyfluid under pressure to increase the speed orpowerof.

said'prime mover in proportion to the pressure of such fluid comprisingin combination with said,

coupling and motor, .acontrol device for supplyingfluid under pressure to and releasing fluid under'pressure from said coupling and motor,-

device being responsive only to pressure of fluid in'excess of that required to initiate eflectiveness of said'coupling to open said other communication to atmosphere and operative at a lower pressure to supply fluid under pressure to said other communication, means connecting both of said fluid pressure controlled devices to said coupling for rendering them responsive to fluid under pressure supplied to operate said coupling, and choke means in the connection between said coupling and said other fluid pressure controlled device ior restricting supply of fluid'under pressure to said other fluid pressure controlled de-' vice.

9. An apparatus for controlling operation of a coupling operable by fluid under pressure to transmit power from a prime mover to drive a load in proportion to the pressure of such fluidand for also controlling a motor operable by fluid under pressure to increase the speed or powerof said prime mover in proportion to the pressure of such fluid comprising in combination with said coupling and motor; a control device for supply ing fluid under pressure to and releasing fluid under-pressure from said coupling-and -motor, two fluid pressure controlled-device's one-respon 17 sive only to a pressure of fluid in excess of that required to provide substantially full effectiveness of said coupling to establish communication between said control device and motor and operative at a lower pressure to close said communication and establish another communication opening said motor to the other fluid pressure controlled device, said other fluid pressure controlled device being responsive only to ressure of fluid in excess of that required to initiate effectiveness of said coupling to open said other communication to atmosphere and operative at a lower pressure to open said other communication to the fluid pressure supply and release communication to said coupling, means for rendering both of sald gfluid pressure controlled devices responsive to fluid under pressure in said supply and release communication, and choke means in the connection between said supply and release communication and said other fluid pressure controlleddevice for restricting flow of fluid under pressure to said other communication and to said other fluid pressure controlled device for controlling operation thereof.

10. An apparatus for controlling operation of a coupling operable by fluid under pressure to transmit power from a primemover to drive a load in proportion to the pressure of such fluid and for also controlling a motor operable by fluid under pressure to increase the speed or power of said prime mover in proportion to the pressure of such fluid comprising in combination with said coupling and motor, a control device for supplying fluid under pressure to and releasing fluid under pressure from said couping and motor, and interlock means arranged to be controlled by fluid under pressure supplied to operate said coupling to establish communication between said motor and control device only when the pressure of the coupling operating fluid is in ,1

excess of a chosen degree corresponding to substantially a full effectiveness of said coupling, and operable when the pressure of coupling operating fluid is less than a chosen lower degree effective upon initiating effectiveness of said coupling, to supply fluid to said motor from the supply to operate said coupling, and means including said interlock means arranged to limit to a chosen degree the pressure of fluid obtained in said motor by the last named supply thereto.

11. An apparatus for controlling two fluid pressure operable couplings for transmitting power from a prime mover to a load in proportion to the pressure of such fluid and for also controlling a motor operable by fluid under pressure to ad-,

just'the speed or power of said prime mover in proportion to the pressure of such fluid, comprising in combination with said couplings and motor, an operators control device for selectively supplying fluid under pressure to operate either one of said couplings and for at the same time releasing fluid under pressure from the other coupling and supplying fluid under pressure to said motor, interlock means controlling communication between said control device and couplings operable by pressure of fluid in each coupling only when in excess of a chosen degree, corresponding to substantial complete ineffectiveness of the respective coupling, to establish communication between the other coupling and said control device, and other interlock means arranged to be controlled by pressure of fluid for operating either coupling for opening communication between said operators control device and motor only when the pressure of fluid in the other coupling is in excess of a chosen degree, corresponding to substantially full effectiveness of the respective coupling, and also operable, only when both of said couplings are substantially ineiiective upon operation of said control device to render either coupling effective, to supply fluid under pressure to said motor, and means for limiting to a chosen low degree the pressure of fluid obtained in said motor by the last named operation of said control device.

12. A control mechanism for a pair of fluid actuators and a third fluid actuator comprising valve means for selectively supplying fluid under pressure to either one of said pair of actuators and at the same time to said third actuator. interlock means for each of said pair of actuators controlled by pressure of fluid in the other of said pair of actuators for closing the fluid under pressure supply communication to and for opening the respective actuator to atmosphere except when the pressure of fluid in the other actuator is less than a chosen degree, and other interlock means for said third actuator controlled by the pressure of fluid in the one of said pair of actuators subject to the higher pressure of fluid for opening said third actuator to atmosphere except when said higher pressure is in excess of u aid chosen degree.

13. A control mechanism for a pair of fluid actuators and a third fluid actuator comprising valve means for selectively supplying fluid under pressure to either one of said pair of actuators and at the same time to said third actuator, interlock means for each of said pair of actuators controlled by pressure of fluid in the other of said pair of actuatorsior closing the fluid under pressure supply communication to and for opening the respective actuator to atmosphere except when the pressure of fluid in the other actuator is less than a chosen degree, and other interlock means for said third actuator controlled by the pressure of fluid in the one of said pair of actuators subject to the higher pressure of fluid for opening said third actuator to atmosphere when said higher pressure of fluid isbetween chosen high and low limits, and to said third actuator and to said higher pressure of fluid when, respectively, in excess of or less than said high or low limits.

ROY R. STEVENS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,326,911 Aikman Aug. 17, 1943 2 404,951 Donaldson July 30,1946 2,426,064 Stevens Aug. 19, 1947 2,444,273 Stevens June 29. 1948 

